Many components are attached to one another by locks integrally formed in one of the components. Such integrally formed locks keep the number of parts required for assembly low and allow some control of stress levels in the components by dimensional control of the components. However, they do not facilitate separation of the components when servicing is required. When an integrally formed lock is damaged, it requires replacement or rework of the component from which it is formed. Furthermore, if the lock is integrally formed with one of the components being fastened, it must be formed of the same material as that component, which results in a compromise in the choice of material between those having characteristics most appropriate for the function of the component and those most appropriate for the locking feature.
Alternatively, many components have been attached to one another by a fastening pin that extends through apertures in the two components and is headed on one end to abut a surface of one component. The fastening pin is typically threaded into the material of the other component. For some installations, particularly where a threaded fastener is threaded into a plastic component, the components may be damaged if excessive torque is applied. Such fastening assemblies may require specialized tooling, such as sensitive torque limited tightening equipment, for assembly or disassembly of the components for those installations where control of the amount of stress experienced by the components being fastened is critical. Furthermore, systems relying on threaded locking systems may be less reliable than abutment-type locking systems when the components are used in environments where significant vibration is experienced.
For example, in a traditional automotive bussed electrical center connection system, there are a series of male blades used to connect the various wiring harnesses to the vehicle. Since the bussed electrical connection-type harness connection is comprised of plastic components, it is considered a “soft” mechanical joint and the bolt is used as a mechanical assist mechanism and not as a compression force driver. The torque limits for such bussed electrical connection-type harness connections may be in the range of three to six newton-meters (3-6 nm), significantly lower than the torque range of typical other fasteners used in vehicle assembly, thus requiring special tools to prevent damage to the comparatively soft plastic components.
Another approach used in some connections is to use a fastening systems having an elongated headed and threaded pin and threading an additional component, such as a nut, onto the back side of the pin. Still another approach is using and elongated member and deforming it on the back side of the components to be fastened. These approaches may be inconvenient or impossible for many installations, such as the bussed electrical connection-type harness connection described above, because they require access to the backside of the fastened assembly, which may be unavailable or difficult to access. They also still may require torque limiting equipment to avoid excessive stress levels.
In light of the foregoing, a need has arisen for a fastener system that is easy to assemble without specialized tooling, facilitates low cost servicing of the components being fastened, minimizes stresses experienced by the components, and provides for a secure assembly of the components in an environment susceptible to vibration.